Canon FD Flange

thingiverse

Taking up Ethan's challenge from his blog post at http://blog.makerbot.com/2011/03/09/pinhole-lens-for-nikon-by-xjcrawler01-and-a-wee-challenge/, I proceeded with my ongoing project that I had initially planned to post only after completion. However, printing at http://metrixcreatespace.com resulted in an inner diameter too small for my Canon 50mm lens. The crucial measurement in the flange is its height; placing it on a lens, your focal length will be 42mm from the bottom to the imaging surface (or 42.14mm from the bottom to the film back). However, an important note while using the original SketchUp file is that it needs scaling up by 10 due to its inability to handle small measurements below 0.1mm. So, where the file displays an inner diameter of 480.0mm, it should be 48.0mm in reality. Post-exporting, a scale down by a factor of 10 ensures accurate measurements.